"Fuck him," Kimmel said when asked about Leno at a panel Monday, Xfinity reports.

Kimmel will face off with both David Letterman and Jay Leno when "Jimmy Kimmel Live" moves to 11:35 p.m. in January. At a 92nd Street Y talk with New York Times writer and late night authority Bill Carter, Kimmel praised Letterman, prompting Carter to ask about Leno.

Kimmel delivered his two-word reply, before saying a “friendship” he once had with Leno was “fake.”

Kimmel and Carter then discussed Kimmel's impersonation of Leno during the 2010 dispute over the "Tonight Show" that led to Leno reclaiming the show from Conan O'Brien.

“I impersonated him on my show,” Kimmel recalled, “and it was the most fun I’ve ever had on my show.”

Leno invited Kimmel on his show the next night, which proved to be a mistake: He asked seemingly inoccuous questions that Kimmel gleefully twisted into insults.

“What was the best prank you ever pulled?” Leno asked, to which Kimmel replied, “I think the best prank I ever pulled was I told a guy that five years from now I’m going to give you my show, and then when the five years came, I gave it to him and then I took it back almost instantly!”